1. Technical Field
The application generally relates to multiple glazing sheet glazing units and, more particularly, to glass blocks. Specifically, the application relates to a glass block having an internal center lite that may be a low-e center lite and/or an internal insulating glazing unit incorporating clear and/or low-e glazing.
2. Background Information
Glass blocks have been used for years in numerous applications. Traditional glass blocks are available in various sizes and thicknesses. All of these sizes and thicknesses have front and rear glass lites spaced apart by a glass sidewall. Glass blocks are formed by heating two block halves to a temperature hot enough to weld or fuse the block halves together when the sidewalls are abutted against one another.
Recent energy conservation requirements encourage the use of a low emissivity coating (low-e coating) on window units to reduce radiant heat transfer. Glass block manufacturers thus desire to add a low-e coating to at least one of the glass block halves or to add an internal low-e coated lite to the interior of the glass block. The step of fusing the glass block halves together will destroy a low-e coating added to a glass block half prior to the fusing step.